warning light FORD MUSTANG 2003 Owner's Guide

DESCRIPTION AND OPERATION
Fuel Tank And Lines
WARNING: Do not smoke, carry lighted tobacco or an open flame of any type when
working on or near any fuel- related component. Highly flammable mixtures are always present
and may be ignited, possibly resulting in personal injury.
The vehicle utilizes a returnless fuel system consisting of:
zthe fuel tank.
z a fuel tank filler pipe which contains a restrictor plate to permit only unleaded fuel to be pumped
into the fuel tank.
z a 1/8 turn fuel tank filler cap.
z a fuel filter providing filtration to protect the fuel injectors.
z a single fuel line accommodating the returnless fuel system.
z a fuel injection supply manifold which contains a differential pressure sensor and a fuel
temperature sensor.
z a fuel pump and sender assembly which provides pressurized fuel to the engine and contains:
„an inlet filter.
„ a check valve which maintains system pressure after the pump is shut off.
„ a pressure relief valve for overpressure protection in the event of restricted flow.
The fuel pump is controlled by an electronic fuel pump driver module which is enabled by the
powertrain control module (PCM). Electrical power to the fuel pump is provided through the inertia fuel
shutoff (IFS) switch, which is located in the luggage compartment. SECTION 310-
01: Fuel Tank and Lines 2003 Mustang Workshop Manual Klj . 1 ba
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REMOVAL AND INSTALLATION
Fuel Tank
Removal
WARNING: Do not smoke, carry lighted tobacco or an open flame of any type when
working on or near any fuel- related components. Highly flammable mixtures are always present
and may be ignited, possibly resulting in personal injury.
WARNING: Fuel supply lines on all vehicles equipped with fuel injected engines will
remain pressurized for long periods of time after engine shutdown. Fuel system pressure must
be relieved prior to fuel system service to prevent possible personal injury or a fire hazard.
1. Disconnect the battery. For additional information, refer to Section 414 - 01 .
2. Relieve the fuel system pressure. For additional information, refer to Section 310 - 00 .
3. Drain the fuel tank. For additional information, refer to Section 310 - 00 .
4. Raise the vehicle. For additional information, refer to Section 100 - 02 .
5. Remove the filler pipe bolt and disconnect the filler pipe hose connections to the fuel tank.
6. Disconnect the fuel tank electrical connector.
SECTION 310-
01: Fuel Tank and Lines 2003 Mustang Workshop Manual Material
Item Specification
Serfactant
(Merpol)
ESE-
M99B144- B Klj . 1 ba
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REMOVAL AND INSTALLATION
Support Straps
Removal
WARNING: Do not smoke, carry lighted tobacco or an open flame of any type when
working on or near any fuel- related components. Highly flammable mixtures are always present
and may be ignited, possibly resulting in personal injury.
WARNING: Fuel supply lines on all vehicles equipped with fuel injected engines will
remain pressurized for long periods of time after engine shutdown. Fuel system pressure must
be relieved prior to fuel system service to prevent possible personal injury or a fire hazard.
1. Remove the fuel tank. For additional information, refer to Fuel Tank in this section.
2. Slide the strap and the retaining pin into the recess and remove the strap retaining pin.
3. Remove the strap.
Installation 1. To install, reverse the removal procedure.
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and when the GEM detects the headlamps or parklamps are on from the exterior lamp circuits. Refer
to the Chime Duration Table in this section for audible output, duration time, and priority ratings.
Safety Belt Warning Chime
The safety belt warning chime and safety belt warning lamp activate when the GEM detects the
ignition switch circuits are in the RUN or START state and when the GEM detects the safety belt is
unbuckled from the safety belt circuit. The safety belt warning lamp indicator will prove out for three
seconds whenever the GEM detects that the ignition circuits make a transition to RUN from OFF, ACC,
or KEYOUT state. Refer to the Chime Duration Table in this section for audible output, duration time,
and priority ratings.
Belt Minder
NOTE:
Belt minder is a configurable item. If configuring using a diagnostic tool, refer to Section 418 -
01 . To configure without using a diagnostic tool, refer to
Belt Minder Deactivating/Activating in this
section.
The belt minder feature supplements the current safety belt warning function. The belt minder feature
is enabled after the current safety belt warning is complete. If the driver safety belt is not buckled
approximately five seconds after the safety belt warning light has turned off, the belt minder reminds
the driver that their safety belt is unbuckled by intermittently sound a chime and illuminating the safety
belt warning lamp in the instrument cluster. While activated, the belt minder alternates the chime and
indicator from on for six seconds to off for 30 seconds.
The belt minder reminder stops when:
zthe drive seat belt is buckled.
z the ignition is turned to OFF or ACC.
z five minutes have elapsed since belt minder has started.
Inspection and Verification
NOTE: Upon installation of a new GEM, the module must be reconfigured. For additional information,
refer to Section 418 - 01 .
1. The warning lamps are a GEM controlled system; refer to Section 419 - 10 .
2. Verify the customer concern by operating the system in question.
3. Visually inspect for the following obvious signs of mechanical and electrical damage.
Chime Duration Table Feature Audible Output Duration Priority
Safety belt Chime, 60/minute 740 Hz 6.0 seconds 1
Key-
in-ignition Chime, 120/minute 740 Hz Continuous 2
Headlamps left on Chime, 240/minute 740 Hz Continuous 3
Airbag Single tone, 1,000 Hz Continuous 4
Door ajar Single tone, 1,000 Hz 1.0 second 7 Klj . 2 ba
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Functionality
With the ignition switch in the RUN position, voltage is applied through the warning indicator I circuit
904 (LG/RD) to the voltage regulator. This turns the regulator on, allowing current to flow from battery
sense A circuit 36 (YE/WH) to the generator field coil. When the engine is started, the generator
begins to generate alternating current (AC) which is internally converted to direct current (DC). This
current is then supplied to the vehicle's electrical system through the output (B+) terminal of the
generator.
Once the generator begins generating current, a voltage signal is taken from the generator stator and
fed back to the regulator internally. This voltage feedback signal (typically half the battery voltage) is
used to turn off the warning indicator.
With the system functioning normally, the generator output current is determined by the voltage of the
A circuit. The A circuit voltage is compared to a set voltage internal to the regulator, and the regulator
controls the generator field current to maintain the correct generator output.
The set voltage will vary with temperature and is typically higher in cold temperatures and lower in
warm temperatures. This allows for better battery recharge in the winter and reduces the chance of
overcharging in the summer.
Battery Positive Output Circuit 38 (B+) (BK/OG)
The generator output is supplied through the battery positive output (B+) terminal on the back of the
generator to the battery and electrical system.
I Circuit 904 (LG/RD)
The I (ignition) circuit is used to turn on the voltage regulator. This circuit is powered up with the
ignition key in the run position. This circuit is also used to turn the charging system warning indicator
on if there is a fault in the charging system operation.
A Circuit 36 (YE/WH)
The A circuit or battery sense circuit is used to sense battery voltage. This voltage is used by the
regulator to determine generator output. This circuit is used to supply current to the generator field
(rotor). The amount of current supplied to the rotor will determine generator output.
Inspection and Verification
WARNING: Batteries contain sulfuric acid. Avoid contact with skin, eyes, or clothing.
Also, shield your eyes when working near batteries to protect against possible splashing of the
acid solution. In case of acid contact with skin or eyes, flush immediately with water for a
minimum of 15 minutes and get prompt medical attention. If acid is swallowed, call a physician
immediately.
WARNING: Batteries normally produce explosive gases which can cause personal injury.
Therefore, do not allow flames, sparks or lighted substances to come near the battery. When
charging or working near a battery, always shield your face and protect your eyes. Always Connector C102a End View
A Circuit 36 (YE/WH)
I Circuit 904 (LG/RD) Klj . 2 ba
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provide ventilation.
WARNING: When lifting a plastic- cased battery, excessive pressure on the end walls
could cause acid to spew through the vent caps resulting in personal injury, damage to the
vehicle or to the battery. Lift with a battery carrier or with your hands on opposite corners.
1. Verify the customer concern by operating the engine to duplicate the concern.
2. Inspect the charging system (battery, generator cable, harness connectors, connections) to determine if any obvious mechanical or electrical concerns exist. If found, repair as necessary
and test the system for normal operation. Refer to the following tables:
3. Check the operation of the charging system warning indicator lamp (instrument cluster). Normal operation is as follows:
zWith the ignition switch OFF, the charging system warning indicator should be OFF.
z With the ignition switch in RUN and the engine off, the charging system warning indicator
light should be on.
z With the engine running, the charging system warning indicator light should be off.
4. Verify the battery is being charged. Carry out the Battery— Load Test. Refer to Component
Tests in this section.
5. If the customer concern is verified after the initial inspection, refer to the Symptom Chart to determine which tests to carry out.
Symptom Chart Visual Inspection Chart
Mechanical Electrical
z
Battery case, posts, hold- down clamp, cables and
connections
z Generator drive (serpentine) belt for condition and
tension. Refer to Section 303 - 05 .
z Generator pulley z
Battery junction box (BJB)
fuse 20 (20A)
z Fuse links
z Circuitry
z Battery charge warning
indicator
z Cables
Normal Charging System Voltages Ignition
Switch
Position A Circuit
36
(YE/WH) I Circuit
904
(LG/RD) Generator B+
Circuit 38 (BK/OG) Battery Engine to
battery
ground Charging
System Warning Indicator
Operation OFF 12V 0V 12V 12V 0V Off
RUN-
engine off 12V 1-
3V 12V 12V 0V Illuminated
RUN-
engine
running 13-
15V 13-
15V 13-
15V 13-15V 0V Off Klj . 3 ba
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Battery—
Drain Tests
NOTE: No production vehicle should have more than a 50 mA (0.050 amp) continuous draw.
Check for current drains on the battery in excess of 50 milliamps (0.050 amp) with all the electrical
accessories off and the vehicle at rest. Current drains can be tested with the following procedure:
WARNING: Do not attempt this test on a lead- acid battery that has recently been
recharged. Explosive gases can cause personal injury.
CAUTION: To prevent damage to the meter, do not crank the engine or operate
accessories that draw more than 10A.
NOTE: Many modules draw 10 mA (0.010 amp) or more continuously.
NOTE: Use an in- line ammeter between the battery positive or negative post and its respective cable.
NOTE: Typically, a drain of approximately one amp can be attributed to an engine compartment lamp,
glove compartment lamp, or luggage compartment lamp staying on continually. Other component
failures or wiring shorts may be located by selectively pulling fuses to pinpoint the location of the
current drain. When the current drain is found, the meter reading will fall to an acceptable level. If the
drain is still not located after checking all the fuses, it may be due to the generator.
NOTE: To accurately test the drain on a battery, an in- line digital ammeter must be used. Use of a test
lamp or voltmeter is not an accurate method due to the number of electronic modules.
1. Make sure the junction box/fuse panels are accessible without turning on interior and underhood lights.
2. Drive the vehicle at least five minutes and over 48 km/h (30 mph) to turn on and exercise vehicle systems.
3. Allow the vehicle to sit with the key off for at least 40 minutes to allow modules to time out/power down.
4. Connect a fused jumper wire between the negative battery cable and the negative battery post to prevent modules from resetting and to catch capacitive drains.
5. Disconnect the negative battery cable from the post without breaking the connection of the jumper wire.
6. NOTE: It is very important that continuity is not broken between the battery and the negative
battery cable when connecting the meter. If this happens, the entire procedure must be
repeated.
Connect the tester between the negative battery cable and the post. The meter must be capable
of reading milliamps and should have a 10 amp capability.
7. NOTE: If the meter settings need to be switched or the test leads need to be moved to another
jack, the jumper wire must be reinstalled to avoid breaking continuity.
Remove the jumper wire.
NOTE: Amperage draw will vary from vehicle to vehicle depending on the equipment package.
Compare to a comparable vehicle for reference.
NOTE: No production vehicle should have more than a 50 mA (0.050 amp) draw. Klj . 11 ba
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DESCRIPTION AND OPERATION
Battery and Cables
Vehicles are equipped with a 12 volt maintenance-
free battery that contains a built-in hydrometer. The
hydrometer eye indication is as follows:
zA green dot means the battery is OK.
z A yellow dot, red dot, or when the green dot is not visible, means the battery needs to be
charged.
WARNING: Batteries normally produce explosive gases which can cause personal injury.
Therefore, do not allow flames, sparks or lighted substances to come near the battery. When
charging or working near a battery, always shield your face and protect your eyes. Always
provide ventilation.
WARNING: When lifting a battery, excessive pressure on the end walls could cause acid
to leak out through the vent caps, resulting in personal injury, damage to the vehicle or the
battery.
WARNING: Keep out of the reach of children. Batteries contain sulfuric acid. Avoid
contact with skin, eyes, or clothing. Also, shield your eyes when working near the battery to
protect against possible splashing of the acid solution. In case of acid contact with skin or
eyes, flush immediately with water for a minimum of 15 minutes and get prompt medical
attention. If acid is swallowed, call a physician immediately.
Ford Motor Company strongly recommends that lead- acid batteries be returned to an authorized
recycling facility for disposal. SECTION 414-
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GENERAL PROCEDURES
Battery Disconnect
WARNING: Batteries normally produce explosive gases which can cause personal injury.
Therefore, do not allow flames, sparks or lighted substances to come near the battery, always
shield your face and protect your eyes. Always provide ventilation. Failure to follow these
instructions may result in personal injury.
WARNING: To avoid accidental deployment and possible injury, the backup power supply
must be depleted before repairing or installing any front or side air bag supplemental restraint
system (SRS) components and before repairing, installing, adjusting or striking components
near the front or side air bag sensors, such as doors, instrument panel, console, door latches,
strikers, seats and hood latches. Failure to follow these procedures may result in personal
injury.
Refer to the appropriate vehicle shop manual to determine location of the front air bag sensors.
To deplete the backup power supply energy, disconnect the battery ground cable and wait at
least one minute. Be sure to disconnect auxiliary batteries and power supplies (if equipped).
Failure to follow these instructions may result in personal injury.
WARNING: When lifting a battery, excessive pressure on the end walls could cause acid
to spew through the vent caps, resulting in personal injury. Lift with a battery carrier or with
your hands on opposite corners. Failure to follow these instructions may result in personal
injury.
WARNING: Keep out of the reach of children. Batteries contain sulfuric acid. Avoid
contact with skin, eyes or clothing. Also, shield your eyes when working near the battery to
protect against possible splashing of the acid solution. In case of acid contact with the skin or
eyes, flush immediately with water for a minimum of 15 minutes and get prompt medical
attention. If acid is swallowed, call a physician immediately. Failure to follow these instructions
may result in personal injury.
1. NOTE: When the battery is disconnected and reconnected, some abnormal drive symptoms
may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven to
relearn its strategy.
Disconnect the battery ground cable.
2. Disconnect the positive battery cable.
3. To install, reverse the removal procedure.
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REMOVAL AND INSTALLATION
Battery
Removal and Installation
WARNING: Batteries normally produce explosive gases which can cause personal injury.
Therefore, do not allow flames, sparks or lighted substances to come near the battery. When
charging or working near a battery, always shield your face and protect your eyes. Always
provide ventilation. Failure to follow these instructions may result in personal injury.
WARNING: Keep out of the reach of children. Batteries contain sulfuric acid. Avoid
contact with skin, eyes, or clothing. Also, shield your eyes when working near the battery to
protect against possible splashing of the acid solution. In case of acid contact with skin or
eyes, flush immediately with water for a minimum of 15 minutes and get prompt medical
attention. If acid is swallowed, call a physician immediately. Failure to follow these instructions
may result in personal injury.
1. Loosen the bolt and disconnect the battery ground cable.
2. Loosen the bolt and disconnect the positive battery cable.
3. Remove the bolt and the battery hold- down.
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